A manual, supposedly dictated by Jesus Christ to a medical psychology professor between 1965 and 1972.
It is what has been considered a channeled book by its believers. It contains both text and exercises in mind training, aimed to teach a student the unimportance of the ego and of the all-importance of God.
The professor who recieved the dictation's name was Helen Shucman. Although raised Jewish, at the time before she began to delve into the dictation of what she would call "the voice," (a silent dictation that she could "hear" without actual auditory hearing) she had considered herself a conservative and an atheist. Someone who was very invested in the values of "society," that the world at large upholds. Values that the course would teach to be mere illusion.
Hinduism as well teaches a main concept of the course, that the limited consciousness is not the true Self and that the man-made world is a mental entanglement and illusion that hinders one from realizing their true universal Self. The Hindu word for this purely physical and mental experience of the lower rather than higher mind is called Maya.
According to the introduction of the book A Course In Miracles, Helen Shucman was involved in a hostile relationship with her colleague William Thetford. The head of her department had confronted them and told them that he was sick of their attitudes. She thought to herself that their must be "a better way." Supposedly A Course In Miracles was this answer.
Like the former Erhard Seminars Training that was more commonly referred to as EST (now integrated into Landmark Education seminars, the most popular being called The forum), it seeks to loosen ones mind from world meanings and teaches that the only meaning that anything has is the meaning that you have taught yourself.
A main difference between a seminar like Landmark's The Forum and A Course in Miracles, besides that one is learned with book and life experience, is that The Forum -- while teaching that you make the meanings for the world and tell the story of your personal history which keeps you grounded to the world you see (as A Course in Miracles would not disagree) -- then continues to uphold and promote the values of The World that the course rejects.
Besides this main difference The Course In Miracles is meant to be a spiritual journey intended to take you far beyond the physical realm and world business and prepare you for eternal life.
Reading this book may result in one of these four possible results:
1.) Experience of extreme spiritual revelation.
2.) Feelings of cynicism and mistrust.
3.) Fear, doubt and anger including asking yourself the question, "Why won't Jesus help me?"
4.) Fear of God and of losing your ego.